Alloy of iron.



No Drawing. Application filed July 29, 1916, Serial No. 112,074. Renewed may 26, 1917.

saa ras manner entice.

. OLIVER B. MO'MILLIN, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR, BY MTESNE ASSIGE- MENTS, TO PITTSBURGH ROLLS CORPORATION,

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COBPQRATION or VIRGINIA.

I ALLOY on 1301s.

Specification of Letters Patent.

Patented Jan. 8, 191.8.

To all whom it may concern:

Be it known that I, OLIVER B. MGMIL- LIN, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Alloys of Iron, of which the following is a specification. i

My invention relates to an alloy of iron, and particularly one in which a high proportion of sulfur is used.

The element sulfur is ordinarily considered a deleterious or weakening element; but I have found that when proportionately combined with the several other elements comprising the present invention, the pres: ence of sulfur in higher proportions than those customarily used, and ordinarily considered objectionable, is not only not harmful, but adds appreciably to the beneficial result of the entire mixture.

In carrying out my invention, Imix with iron,.either in an air furnace or open hearth furnace, or in a cupola or any other suitable heating furnace, proportions of silicon, sulfur, phosphorus, manganese and chromium, as hereinafter stated, together with a content of total carbon,

within the ranges stated. v

Suitable proportions of these severalmetallic elements are as follows, it being understood that minimum and maximum proportions are givenin percentages, and that the remaining quantum of material to make up the entire 100% is ordinary gray or foundry .iron or scrap metal:

Silicon .25% to 1. 00% Sulfur 05% to 2. 00% Phosphorus 05% to 2. 00% Manganese .20% to 1. 00% Chromium 25% to 3.00%

Total carbon 1.50% to 3.

The alloy within the above stated proportions is particularly adapted for the making of plate mill rolls, sheet mill rolls, rolls, and other rolls or similar articles requiring a hard, resisting, dense surface of signature in the tin plat-e considerabe depth, adapted to resist abrasion and wear.

The especial quality of the sulfur content is that it increases the depth of chill in proportion to the amount of sulfur used, especially in combination with the accompanying content of chromium.

The percentages .of the alloying metals rriay be varied Within the minimum and maximum limits above given, according to the desired result. Thus I have secured excellent results in the manufacture of 'rolls with a preferred mixture made as follows:

Silicon .50% J Sulfur .12% Phosphorus .08% Manganese 30% Chromium 1.00% Total carbon 2. 40% Iron 95.60%

The alloying elements re-act. and combine upon and with each other, producing the metallurgical results, molecular changes, and resulting effects desired, avoiding undue brittleness, and producing in the resulting casting a characteristic hard, dense, and deeply penetrating outer .body portion for the roll, hammer die, anvil, or other article into which the mixture is formed.

Having described my invention, what I claim is:

1. An alloy composed of iron combined with silicon ranging from 25% to 1;00%, chromium from 25% to 3.00%, sulfur 05% to 2.00%, phosphorus .05% to 2.00%, inanganese .-20% to 1.00%, total carbon 1.50%

2. An alloy composed of silicon 50%, sulfur 12%, phosphorus .08%, manganese 30%, chromium 1.00%, total carbon 2.40% and iron 95.60%.

In testimony whereof I hereunto affix my presence of two witnesses. OLIVER B. MCMILLIN.

Witnesses C. CLARKE,

' W. A.'HECKMAN.

Serial No. 

